M'kay, here is my fan made walkthrough!
Just a heads up, from the prologue all the way to the end of version 1.3, there are a shit load of extra choices added to the game. Now don't panic, none of these choices affect anything in the game...yet. I have a feeling that in the future, you're going to have to replay the game from the beginning when these choices do matter.
I haven't played the game in a few updates, I only have looked at the code, and I see no way to avoid Rose's hunger for Jason's cock. Either you're part of the party or you are not. As for the comment that she doesn't make sense as interested in Jason, remember when you were locked out of your and Anna's room? Jason walked by and Rose obviously was pining after him so I would argue she makes total sense to jump on Jason's boner when she has the chance.
Anyway, I just look at code and write walkthroughs, not write the game. Enjoy!